Ink drying reflector system

ABSTRACT

The invention relates to a radiator in which there is an elliptical reflector, part of which is formed by two spaced apart plates forming ducting, the ducting being pivotable from a first, open, position to a second position in which the radiation from the radiator is cut-off, cooling fluid being drawn through the ducting to cool the reflector.

United States Patent 1191 Knight Aug. 27, 1974 INK DRYING REFLECTORSYSTEM 2,855,190 10/1958 Rieger 432/45 3,421,746 1/1969 McCoy 432/8 [75]Inventor- Rollald Edward Kmght, 3,452,181 6/1969 Stryjewski 219/216Maldenhead, England 3,492,458 1/1970 White et a1. .1 219/216 3,600,5538/1971 Costello [73] Asslgnee' g z g d 3,697,722 10/1972 Furuichi et al.mg am an 3,700,213 10/1972 Laisney [22] Filed: July 17, 1972 3,733,7095/1973 Bassemir et al .1 34/4 3,745,307 7/1973 Peek, Jr. et al 34/4 [2]]Appl. No.: 272,644

Primary Examiner-John .l. Camby [30] Foreign Application Priority DataAssistant Examiner-Henry C. Yuen July 16, 1971 01661 Britain 33500/71Attorney Agent, Blanchard and Flynn [52] US. Cl 34/4, 219/348, 219/388,

432/55, 34/7 57 ABSTRACT 51 1m. 01. F26b 3/28 [53] Field of Search432/50, 35 5 5, 3 8, 4246, The 1nvent1on relates to a radlator 1n whlchthere 1s an 2 5 57 64, 5 9 2 2 7 0 8, elliptical reflector, part ofwhich is formed by two 22 219/21 347 34 3 34/1 2 49 4 spaced apartplates forming ducting, the ducting being 3 1 4, 7 pivotable from afirst, open, position to a second position in which the radiation fromthe radiator is cut-off, [56] References Cited cooling fluid being drawnthrough the ducting to cool UNITED STATES PATENTS reflecor' 2,664,28212/1953 Mann 432/8 10 Claims, 2 Drawing Figures INK DRYING REFLECTORSYSTEM The invention relates to radiator fittings and to apparatus forcooling a fittings housing, for example, are discharge tubes,particularly those with a high rating. Such fittings are often used fordrying printing inks on paper or other materials.

At the present stage of development of ultra-violet ink dryers forprinting it is necessary to use a high intensity are (for example 200watts per inch) and to focus the power of the arc in a concentrated areaon a moving substrate with the printing ink thereon.

A serious drawback to this prior arrangement 'is that the Infra-Redcontent of the radiation emitted from the tube is also focussed and theheat concentration is such that if the paper should stop or even slowdown, it often ignites.

Any barrier interposed between the radiator and the substrate willlikewise be subjected to a degree of heat concentration depending on itsdistance from the radiator and from the focussing point on thesubstrate. This concentration 0of heat is likely at best to seriouslydistort the barrier.

Also, because of the limited space available in the majority ofinstallations, it is necessary that any shutter or barrier takes upminimal space.

Because of the time lag in restarting the are when extinguished, it isconsidered undesirable to switch off the arc to overcome the aboveproblem.

According to the invention there is provided apparatus for cooling aradiator fitting, comprising ducting which is adapted for movement to aposition in which radiation from the radiator is substantially cut offand in which cooling fluid passes through the ducting so that thefitting is cooled.

In a preferred embodiment the ducting may comprise a first platecomprising part of a reflector for the radiator and a second platespaced from the first plate by a diaphragm, the two plates being closertogether at an inlet for the cooling fluid than at an outlet for thecooling fluid.

The radiator may be an arc tube mounted in a housing and situated withinan elliptical reflector, the first plane comprising a part of thereflector. Moreover, the reflector may include perforations to enhancecooling of the fitting.

In a position in which radiation from the radiator is not cut off, theducting may preferably by situated adjacent a wall of the housing, andin the second position cooling fluid, which may be air, may also passthrough the ducting. The ducting may move by pivoting between the twopositions on a pivot pin extending longitudinally along the housing in adirection substantially parallel with the arc tube.

A suitable radiator temperature is maintained in the closed position sothat the radiator may return to full power when the ducting is retractedto the second position. One means of achieving this is to reduce the,

power into the radiator in the closed position. Altematively theventilation may be increased ora combination of both methods may beutilized.

The ducting may be controlled automatically so that the radiator may beenclosed and the radiation cut-off when substrate moving beneath theradiator stops or slows down, so that heat damage to the substrate maybe substantially obviated. This is particularly so when the radiator isused to dry ultra violet sensitized printing ink impressed on paper orother substrate moving in the focussed energy of the reflector, in whichcase ultra-violet energy from the radiator causes drying or curing ofthe ink.

One embodiment of the invention is diagrammatically illustrated, by wayof example in the accompanying, wherein:

FIG. 1 shows a transverse cross-section through a radiator fitting usedto dry printing ink on paper passing below the fitting, and FIG. 2 showsa fragment of FIG. 1 and discloses a possible modification of thepresent invention.

The radiator fitting 1 includes a radiator 2 which comprises a 5 KW arctube, two feet long and emitting ultra-violet ene gy, mounted in ahousing 3 which has an inlet 4 for cooling air and an extraction duct 5for the air. The extraction duct 5 is in connection with a suction fan18. The housing 3 includes an elliptical reflector 6 of high polishedanodized aluminium. The reflector comprises a fixed upper section 7 andtwo side wall sections 8. Each side wall section forms a first plate ofa cooling duct 9 and is spaced apart from a second plate 10 by adiaphragm or spacer 11. The mouth 12 of each cooling duct isapproximately one ince across and is narrower than the exit, which is acommunication with the extraction duct 5.

Each cooling duct is pivotably mounted on a pivot pin 13 extending thelength of the housing and is capable of pivoting from, a first position,shown in heavy lines in the drawing, in which the respective coolingduct is hinged inwardly to cut off substantially the radiation emittedfrom the radiator 2 and a second position, shown in faint lines, inwhich the cooling ducts are adjacent a wall of the housing, the firstplate of each duct then forming part of the elliptical reflector. In thesecond position, the path through each cooling duct is partiallyobstructed by a flange 14 on the housing. Moreover, the reflector mayhave perforations (not shown) which facilitate cooling.

Use of the apparatus is described assuming the radiator l is used to dryprinting ink impressed on paper (not shown) passing through the focussedenergy 15 of the elliptical reflector, as shown by the arrows X.

Assuming the printing machine is functioning normally, the cooling ducts9 are in the second position shown by faint lines, and the radiator isemitting ultraviolet energy at full power to dry the ink. Cooling air issucked into the lamp housing around the flanges l4 and through the ducts9 to the extraction duct 5.

If the paper now slows down or stops, a sensor, for example a minimumpaper speed sensor or a heat sensor, is actuated to operate a motor,solenoid, hydraulic means or any other suitable means, which rotates thecooling ducts 9 to the closed position shown in heavy lines so thatradiation from the radiator is cut off, while cooling air is drawnthrough the cooling ducts, over the reflector and out through theextraction duct. Cooling air also enters the triangularly shaped tunnelE" formed by the closed ducts 9 and the section 7, and through theperforations if utilized. Air escapes from the tunnel E through theperforations, and through gaps D.

The cooling ducts thus function to shut off the energy and to cool thefitting. Moreover, when the ducts pivot inwardly to the first position,they may automatically actuate a switch to reduce the power of theradiator, while at the same time the tunnel causes the temperature ofthe arc to be maintained to permit immediate operation when the coolingducts are returned to the second position.

When the paper or substrate is again moving at a sufficiently highspeed, the cooling ducts are retracted to the walls of the housing andthe radiation again falls on the paper or substrate. Simultaneously andinstantaneously the radiator is stepped up to a suitable operatingpower.

The first plates 8 of each cooling duct 9 may include flexible sealstrips, as shown at 16, and there may be a seal 17 between the coolingducts and the housing as shown in FIG. 2.

The invention thus provides the following advantages: 1. Compactarrangement. 2. Using Reflector as shutter saves space and eliminatesother parts. 3. Closing of reflector de-focuses a large area of thereflective surface and therefore spreads heat more evenly. 4. Movementof air path with shutter ensures adequate surface cooling in closedposition.

I claim:

1. Apparatus for cooling a radiator fitting used for drying a web,comprising a housing, reflector means and radiator means, the radiatormeans being housed in the housing and enclosed by said reflector meanswhich is also wholly in the housing, and extraction duct means includinga first part communicating with extraction fan means and with theinterior of the housing between said housing and said reflector means,and including in said housing pivot means extending substantiallyparallel to the radiator means, parts of said reflector means beingpivotable on respective ones of said pivot means, said pivotable partsof said reflector means each comprising a first plate means and a secondplate means spaced therefrom to form a further part of said extractionduct means having inlet means and outlet means, which outlet meanscommunicates with said first part of said extraction duct means andthrough which cooling air can flow from said inlet means to said outletmeans, said pivotable parts of said reflector means being movable from aposition adjacent said housing to a position in which radiation fromsaid radiator means is substantially cut off with said cooling air beingfreely flowable through said pivotable reflector parts in both of saidpositions.

2. Apparatus as defined in claim 1, wherein said inlet means is of lessdimension between said first plate and said second plate than is saidoutlet means.

3. Apparatus as defined in claim 1, wherein said reflector means iselliptical and said first plate means forming part of the reflectivesurface of said reflector means.

4. Apparatus as defined in claim 3, wherein there is flexible stripmeans, said flexible strip means being secured to edge means of saidfirst plate means.

5. Apparatus according to claim 1, wherein said reflector means includesa stationary center portion, said parts each being tubular and beingdisposed on opposite sides of said center portion, and said pivot meansdefining pivot axes located closely adjacent the opposite edges of saidcenter portion.

6. A reflector-type dryer, particularly for drying a moving web,comprising:

housing means defining therein a chamber open at one end;

curved reflector means positioned within said chamber and having aninner concave reflective surface directed toward the open end of saidchamber;

said reflector means including a first portion stationarily positionedrelative to said housing means and a second portion pivotally mountedrelative to said first portion for swinging movement between an openreflective position and a closed position wherein said second portionand the remainder of said reflector means form a substantially closedtunnel-like compartment, said second portion being positioned whollywithin said chamber when in said open and closed positions;

radiator means disposed within said chamber in front of said reflectivesurface, said radiator means being positioned so as to be within thetunnel-like compartment when said second reflector portion is in saidclosed position;

a cooling system for said dryer including an exhaust duct;

said second reflector portion including first and second spaced wallswhich are fixed relative to one another and define therebetween a ductwhich is part of said exhaust duct of said cooling system and has inletand outlet openings adjacent the opposite ends thereof for permittingflow of cooling fluid therethrough, the inlet opening being disposedclosely adjacent and directed substantially toward the open end of saidchamber, and one of said walls constituting a portion of said reflectivesurface when said second reflector portion is in said open position; and

said housing means including wall means defining a stationary part ofsaid exhaust duct communicating with a portion of said chamber adjacentthe outer surface of said reflector means, said outlet openingassociated with said second reflector portion communicating with saidportion of said chamber.

7. A dryer according to claim 6, wherein said reflector means includes athird reflector portion disposed wholly within said chamber andpivotally mounted relative to said first portion for swinging movementbetween an open reflective position and a closed position, said firstreflector portion being disposed between said second and third reflectorportions whereby said second and third reflector portions are swingabletoward one another as they are moved toward their respective closedpositions, said three reflector portions coacting to form said closedtunnel-like compartment.

8. A dryer according to claim 7, wherein said third reflector portionalso includes first and second spaced walls fixed relative to oneanother and defining a duct therebetween having inlet and outletopenings adjacent the opposite ends thereof, the inlet opening of saidlatter-mentioned duct being disposed adjacent and directed substantiallytoward the open end of said chamber and the outlet opening of saidlatter-mentioned duct communicating with said portion of said chamber.

9. A dryer according to claim 8, wherein said second reflector portionis mounted for swinging movement about a hinge axis located closelyadjacent one edge of said first reflector portion, wherein said thirdreflector portion is mounted for swinging movement about a hinge axislocated closely adjacent the other edge of said first reflector portion,and wherein the outlet opening associated with each of said second andthird of said tubular member being positioned closely adjacent the openend of said chamber, and the outlet opening defined adjacent the otherend of said tubular member being disposed closely adjacent said firstreflector portion and communicating with a portion of said chamberlocated rearwardly of said first reflector portion.

1. Apparatus for cooling a radiator fitting used for drying a web,comprising a housing, reflector means and radiator means, the radiatormeans being housed in the housing and enclosed by said reflector meanswhich is also wholly in the housing, and extraction duct means includinga first part communicating with extraction fan means and with theinterior of the housing between said housing and said reflector means,and including in said housing pivot means extending substantiallyparallel to the radiator means, parts of said reflector means beingpivotable on respective ones of said pivot means, said pivotable partsof said reflector means each comprising a first plate means and a secondplate means spaced therefrom to form a further part of said extractionduct means having inlet means and outlet means, which outlet meanscommunicates with said first part of said extraction duct means andthrough which cooling air can flow from said inlet means to said outletmeans, said pivotable parts of said reflector means being movable from aposition adjacent said housing to a position in which radiation fromsaid radiator means is substantially cut off with said cooling air beingfreely flowable through said pivotable reflector parts in both of saidpositions.
 2. Apparatus as defined in claim 1, wherein said inlet meansis of less dimension between said first plate and said second plate thanis said outlet means.
 3. Apparatus as defined in claim 1, wherein saidreflector means is elliptical and said first plate means forming part ofthe reflective surface of said reflector means.
 4. Apparatus as definedin claim 3, wherein there is flexible strip means, said flexible stripmeans being secured to edge means of said first plate means. 5.Apparatus according to claim 1, wherein said reflector means includes astationary center portion, said parts each being tubular and beingdisposed on opposite sides of said center portion, and said pivot meansdefining pivot axes located closely adjacent the opposite edges of saidcenter portion.
 6. A reflector-type dryer, particularly for drying amoving web, comprising: housing means defining therein a chamber open atone end; curved reflector means positioned within said chamber andhaving an inner concave reflective surface directed toward the open endof said chamber; said reflector means including a first portionstationarily positioned relative to said housing means and a secondportion pivotally mounted relative to said first portion for swingingmovement between an open reflective position and a closed positionwherein said second portion and the remainder of said reflector meansform a substantially closed tunnel-like compartment, said second portionbeing positioned wholly within said chamber when in said open and closedpositions; radiator means disposed within said chamber in front of saidreflective surface, said radiator means being positioned so as to bewithin the tunnel-like compartment when sAid second reflector portion isin said closed position; a cooling system for said dryer including anexhaust duct; said second reflector portion including first and secondspaced walls which are fixed relative to one another and definetherebetween a duct which is part of said exhaust duct of said coolingsystem and has inlet and outlet openings adjacent the opposite endsthereof for permitting flow of cooling fluid therethrough, the inletopening being disposed closely adjacent and directed substantiallytoward the open end of said chamber, and one of said walls constitutinga portion of said reflective surface when said second reflector portionis in said open position; and said housing means including wall meansdefining a stationary part of said exhaust duct communicating with aportion of said chamber adjacent the outer surface of said reflectormeans, said outlet opening associated with said second reflector portioncommunicating with said portion of said chamber.
 7. A dryer according toclaim 6, wherein said reflector means includes a third reflector portiondisposed wholly within said chamber and pivotally mounted relative tosaid first portion for swinging movement between an open reflectiveposition and a closed position, said first reflector portion beingdisposed between said second and third reflector portions whereby saidsecond and third reflector portions are swingable toward one another asthey are moved toward their respective closed positions, said threereflector portions coacting to form said closed tunnel-like compartment.8. A dryer according to claim 7, wherein said third reflector portionalso includes first and second spaced walls fixed relative to oneanother and defining a duct therebetween having inlet and outletopenings adjacent the opposite ends thereof, the inlet opening of saidlatter-mentioned duct being disposed adjacent and directed substantiallytoward the open end of said chamber and the outlet opening of saidlatter-mentioned duct communicating with said portion of said chamber.9. A dryer according to claim 8, wherein said second reflector portionis mounted for swinging movement about a hinge axis located closelyadjacent one edge of said first reflector portion, wherein said thirdreflector portion is mounted for swinging movement about a hinge axislocated closely adjacent the other edge of said first reflector portion,and wherein the outlet opening associated with each of said second andthird reflector portions is located closely adjacent the respective edgeof said first reflector portion.
 10. A dryer according to claim 7,wherein each of said second and third reflector portions compriseelongated tubular members having said inlet opening defined adjacent oneend thereof and said outlet opening defined adjacent the other endthereof, each of said tubular members defining said duct extendingtherethrough, the inlet opening defined adjacent the one end of saidtubular member being positioned closely adjacent the open end of saidchamber, and the outlet opening defined adjacent the other end of saidtubular member being disposed closely adjacent said first reflectorportion and communicating with a portion of said chamber locatedrearwardly of said first reflector portion.